PPT-30
Green Earth Movement
An E-Newsletter for the cause of Environment, Peace, Harmony and Justice
Remember - “you and I can decide the future”
RISING
SEA
LEVELS
Sea-level rise is one of the most concerning
consequences associated with global climate change,
thanks to melting polar ice and thermal expansion
caused by warming ocean waters - and we're already
starting to see its effects on coastal communities
around the world.
Global average sea level rose roughly eight inches
from 1880 - 2009.
The average annual rate of global sea level rise
accelerated from 1993 - 2008, increasing 65 - 90
percent above the
twentieth century
average. The U.S. East
Coast and Gulf of
Mexico experienced
some of the world's
fastest rates of sea
level rise in the twentieth century due to local and
regional factors.
The US Geological Survey
estimates that if all the
world's glaciers melted,
sea level would rise by
about 80 meters, or more
than 260 feet. This
scenario could be
thousands of years in the future, but it would
render many of the world's best-loved
coastal cities unrecognizable.
Global warming is the primary cause of current
sea level rise. Human activities, such as burning
coal and oil and cutting down tropical forests,
have increased atmospheric concentrations of
heat-trapping gases and caused the planet to
warm by 1.4 degrees Fahrenheit since 1880.
Rising temperatures are warming ocean waters,
which expand as the temperature increases.
This thermal expansion
was the main driver of
global sea level rise for
75 - 100 years after the
start of the Industrial
Revolution, though its
relative contribution has declined as the
shrinking of land ice has accelerated.
Land ice—glaciers, ice caps, and ice sheets—is
shrinking at a faster rate in response to rising
temperatures, adding water to the world's oceans.
As the rate of ice loss has accelerated, its contribution
to global sea level rise has increased from a little
more than half of the total increase from 1993 - 2008
to 75 - 80 percent of the total increase between 2003
- 2007.
Sea level will rise
significantly over the
coming century. Our
past heat-trapping
emissions have
committed us to
continued sea level
rise over the coming decades, but our present
and future emissions choices can affect the rise
in seas and the pace at which it unfolds beyond
2050.
As global temperatures continue to rise,
ice in the polar regions and glaciers will
melt, dumping tons of extra water into
the ocean. Warmer water temperatures
will also lead the oceans to expand.
These factors will cause sea levels to
increase and swamp coastal areas all
over the world.
Although flooding is the obvious
consequence of rising sea levels, there
are plenty of other effects to consider
— none of them good.
Here are five of those effects you
probably haven't thought about:
1. It will contaminate our drinking water
As the rising sea crawls farther and farther up the shore, in
many places it will seep into the freshwater sources in the
ground that many coastal areas rely on for their drinking
water. These underground water sources, called aquifers, are
crucial springs of freshwater — in fact, groundwater accounts
for most of the planet's freshwater.
Saltwater is unsafe to drink, and while
it is possible to remove the salt from
water, doing so is an expensive and
complicated process. Some
communities are already investing
in costly desalination plants in
anticipation of hard times ahead.
2. It will interfere with farming
Those same freshwater sources we use for drinking
also supply the water we use for irrigation. The
problems here are the same: The intruding sea could
make these groundwater sources saltier. Saltwater
can stunt or even kill crops, but creating freshwater
from saltwater is a costly and unsustainable practice.
In a twist of irony,
recent research has
suggested that pumping
freshwater from the
ground for human use
may actually be
contributing to a rise in sea levels. After the
groundwater has been used — for drinking,
irrigation, or other industrial purposes — it is often
discarded into the ocean, where it adds to the
already-growing volume of water lapping at our
shores.
3. IT WILL CHANGE OUR COSTAL PLANT LIFE
More saltwater hitting our shores will change the chemistry
of the soil on the coast, meaning the plant life there will most
likely change as well. Plants are really sensitive to their
environments. Air temperature, access to water, and the
chemical characteristics of soil are all
factors that influence whether a plant
can thrive in a given location. As rising
ocean water seeps into the ground, the
soil near the coast will become saltier.
Some plants will simply be unable to
cope with the change in soil salinity and
may disappear from the shoreline.
Trees have to work harder to pull water out of
salty soil; as a result, their growth can be
stunted — and if the soil is salty enough, they
will die, a common sign of sea level rise. Even
trees that are especially suited to salty soil can't
survive repeated flooding by seawater.
4. IT WILL THREATEN WILD LIFE POPULATIONS
Many forms of wildlife make their home on the beach. As the
rising ocean erodes the shoreline and floods the areas in
which coastal animals live, animals like shorebirds and sea
turtles will suffer. Their delicate nests may be swept away by
flooding, an especially big
problem for endangered
animals like sea turtles that
can't afford to lose any
offspring. Their habitats
may be so damaged by
flooding or changes in the
surrounding plant life that
they can no longer survive
in the environment.
5. It will hurt the economy
The tourism and real-estate industries in coastal
areas are likely to take a hit as prime beachfront
properties and recreational areas are washed
away by rising waters. This is a fact that some
involved in these industries are finding hard to
swallow.
Even if global warming emissions were to drop
to zero by 2016, scientists project another 1.2 to
2.6 feet of global sea level rise by 2100 as
oceans and land ice adjust to the changes we
have already made to the atmosphere.
Projections for global sea
level rise by 2100 range
from 8 inches to 6.6 feet
above 1992 levels, though
the lowest end of this range
is a simple extension of
historic sea level rise—and
recent data indicate this rate has nearly doubled in
recent years.
The rate and magnitude of the loss of ice sheets,
primarily in Greenland and West Antarctica, will have
the greatest effect on long-term sea level rise.
1] We must prepare for rising seas and work to
limit the long-term pace and magnitude of sea
level rise by dramatically reducing global
warming emissions. Communities must weigh
the costs and risks of accommodating the
rising seas, retreating
from them, or trying
to defend coastal
properties and
infrastructure with
protective measures.
2] Traditional
Defensive approaches
-such as building
seawalls and levees,
or replenishing sand
along eroded beaches
-can help protect
against flooding and
damage but may not provide adequate or
sustainable long-term protection.
3] Maintaining or restoring natural
buffers, such as barrier islands, tidal
wetlands, and mangroves, can also
help defend coastlines.
4] Measures like elevating and floodproofing
structures
can
help
accommodate temporary flooding and
gradual inundation.
5] The most vulnerable coastal
communities may increasingly need to
consider the stark option of some form
of retreat from the rising seas.
6] To limit the long-term risks of sea level
rise and the costs of adapting to it, we
must work toward deep reductions in the
Global warming emissions that are the
primary cause of rising sea levels.
This educational PowerPoint Presentation (editable) is
prepared by GEM Team (courtesy: internet).
For other similar GEM PowerPoint Presentations on various
environmental issues see next slide.
These PPTs may be downloaded from our website
www.stfrancisxavierpanvel.in
The GEM PPTs can be creatively used for various groups
like school/college students, NGOs, government officials,
Church groups, SCC groups, housing society members
and so on.
Zero Garbage
Solar Energy
Junk Food
Twenty Tips To Save Nature
Plastic – a boon or bane?
Green Passion
Soft drink – A Health Hazard
Waste to energy
Rain Water Harvesting
Eco-friendly Religions
Happy Green Diwali
Climate Change
The future of Biodiversity
Genetically Modified Foods
Waste Water Treatment
Give thanks, Give Life (Body,
Organ, Tissue Donation)
Organic Farming
Waste to cooking gas
Reduce, Reuse. Recycle
Protect Mangroves
Say NO to Bottled water
Save Lakes and Ponds
Forests are green lungs
Coal Mining and Ecology
Sin of Food Waste
Climate change and Poverty
Stop Water Pollution
Carbon Footprints
Parks and Open Spaces
Rising Sea Levels
For Free Weekly GEM E-Newsletters visit –
www.stfrancisxavierpanvel.in – every
Friday. Go to GEM section,
click GEM E-NEWSLETTERS